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No. 608,693. Patented Aug. 9, |898. J. H. LUDWIG.

PIANOFORTE.

(Application filed Aug. 28, 1897.)

(No Model.)

UNITED STATES PATENT OFFICE.

JOHN Il. LUDVIG, OF NEWT YORK, N. Y.

PIANOFORTE.

SPECIFICATION forming part of Letters Fatent N o. 608,693, dated August 9, 1898.

Application iilcd August 28, 1897. Serial No. 649,813. (No model.)

T0 n/ZZ 1,077,071@ t may concern:

Beit known that I, JOHN H. LUDWIG, a citizen of the United States, and a resident of the city of New York, in the county of New York and State of New York, have invented certain new and useful lmprovementsin Pianofortes, of which the following is a specification.

This invention relates to improvements in pianofortes, and especially to the scale-bridge bar of the same.

The object of my invention is to provide a new and improved adjustable scale -bridge bar which extends acrossV the strings on the sides at which the hammers are located, and

which bridge-bar is adjustable as to its bearing upon the strings, thus permitting' of adj usting or regulating the pressure of the bridge-bar on the strings and thereby the pressure of the strings on the wooden bridge on the sounding-board, and thereby permitting of restoring to the sounding-board its full vibratory power at all times and rendering the tone fuller, sounder, less metallic, and of more beauty than has been possible in the pianos as constructed heretofore.

ln the accompanying drawing, forming a part of this specification, a vertical transverse sectional view through part of the sounding-board and metal frame and through the scale-bridge bar is shown, parts of the latter being in perspective View.

The pianoforte has the conventional metal frame A, which, however, is provided at the top with the shoulder B, which rests and bears against the wooden Wrest-plank C of the wooden frame, and above said shoulder the metal frame A has an upward extension D in a plane in front of that of the plate proper, said extension resting on the wooden plank or bar C, as shown, and to which it is fastened by screws. (Not shown.)

Heretofore that part of the metal frame A resting against the wooden plank or bar C was in the same plane as the rest of the frame A, whereas in my construction it is in a plane in advance of the frame proper, for a purpose that will be set forth hereinafter.

The tuning-pins E are driven through suitable holes in the frame extension D into the plank or bar U, as shown.

The strings F are secured at one end to metal pegs or pins G on the frame A in the usual manner, and their other ends are secured to the tuning-pins E, and the strings rest on and bear against the wooden bridge H, secured on the sounding-board J, as in the pianos as constructed heretofore.

The scale-bridge bar K, made of metal, pa

pier-mache, or any other suitable hard4 substance, extends across the strings F on the outer sides-that is, on the sides on which the hammers L strike-and is preferably provided along the lower edge with a lip M, which comes in contact with the strings, and at its upper edge and inner side it rests on a series of pins or analogous supports N, secured to and projecting upward from the plate A.

Screws O or analogous devices are used to hold the scale-bridge bar K in place and to press its lip M against the strings F. The screws are screwed into the plate A, or, if desired, they may be screwed into a wooden block interposed and secured between the frame A and the sounding-board.

By means of the screws O or analogous adj usting devices the lip M of the bridge-bar K is tilted toward and pressed against the strings F, which at the point of Contact with said lip are pressed toward the frame A and sound ing-board J, and for this reason the timingpins E must project a greater distance from the plane of the frame A, so as to permit of an inward inclination from the pin to the lip M, as shown at F. In order to take up the strain of these extended pins E, the extension D has been located in a plane in advance of that of the frame A proper.

The hammers L strike the strings F at points of desired striking distances varying with the length of the string from the lip M, and the strain produced by the impact is in the same direction as that produced by the lip M. The scale-bridge can be made of a single continuous piece, but is preferably made in sections, conforming in size to the distance between the braces on the frame A. It is evident that with this construction the greater part of the force of the concussion by the blow of the hammer is transmitted to wooden bridge Il, and by the latter to the soundingboard J, whereas in the pianos heretofore which have a rigid scale-bridge over which the strings pass a great part of the force of concussion by the hammer-blow is taken up IOO by the rigid bridge and hence is lost. On account of the absence of this rigid bridge in my construction the tone is much improved in power and expansion for the reason that the full benefit of the hammer-blow is transmitted to the sounding-board.

The sounding-board is rendered much more sensitive, and thus instantly responsive.

As the piano becomes older and the sounding-board relaxes from the strain of the strings pressing on the sounding-board bridge and sounding-board, the necessary strain or pressure of the strings being removed thereby can be readily increased or restored and adjusted by screwing the bridgebar K down more firmly toward the strings and the original relationship and the full original vibratory power of the sounding-board restored in a most simple and effective manner. The strain on the strings is also reduced by my improved bridge-bar, as there is only one point of friction on lche strings between the wooden bridge and the tu ning-pins, and thus tuning is greatly facilitated.

I-Iaving thus described my invention, what I claim as new, and desire to secure by Letters p Patent, is

l. In a pianoforte, the combination with the metal frame and sounding-board and the usual wooden bridge on the sounding-board, of pins and tuning-pins, of strings secured to the said pins and resting on the bridge only and on no other support between their attaehments to the pins, and an adjustable scale-bridge bar resting on the strings between the tuning-pins and the wooden bridge, and means for adjusting the pressure of said bridge-bar on the strings, substantially as herein shown and described.

2. In a pianoforte, the combination with a Wrest-plank, of a metal frame having a shoulder and an extension beyond said shoulder, the shoulder resting against one edge of the plank and the extension on the adjacent face of the plank, tuning-'pins passed through said extension into the plank, strings attached to said tuning-pins, and an adjustable bridgebar extending across and resting on said strings, substantially as herein shown and described.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 20th day of August, 1897.

JOHN H. LUDWIG.

W'itnesses:

CHAs. A. ERICSSON, FRED KNECHT. 

